At some point everything comes back to the beginning. It's a cycle. Pure and simple.
I believe in karma, sometimes more than others but still, I believe in it. And, if we think about it, what we consider karma it's in reality a cycle.
One of the quotes I have on computer desktop is "Karma's a bitch" and I must say.. I love that quote. I some cases I think it takes too long but karma always has its way towards people and their actions. We may see some people who are successful and "happy" because they diminish others and use them to get higher in life but I promise you that someday they'll suffer the consequences. You may not notice it or even know but they will, maybe later than sooner but it will happen.
But the way I see it karma doesn't work just for one side. It also happens to what we may consider "good" people. To those who always care for the others and help them without being selfish and second intentions... How could karma not work for them? We always need a balance in life.
Karma. It's the way world works in my opinion. What we experience is often the result of what we did before. If something really bad happens and we are not sure what we did to cause that.. maybe... maybe it's because something great is coming along and expecting you.
It's just a way of facing life. Just a theory. My theory at least.